The present invention relates to an electronic purse loan system or POS terminal for storing loan data relating to a shortage in the amount of a payment to a center and for effecting a processing to clear off a loan amount in the next transaction when a commercial transaction is performed using the electronic purse loan system or POS terminal.
If a commercial transaction is performed using a prepaid card of the type which is in widespread use at the present time, such as a telephone card, the above-described system operates to inhibit a commercial transaction involving use of the card at that time when the total consumed amount reaches or exceeds the sum stored in the card.
In addition, an electronic purse system has been developed in which a transaction is performed by recording information concerning the charges for transaction in an IC card, for example; however, in such an electronic purse system, a transaction may be performed only to the extent of the sum payable from an electronic purse, as described in Japanese published unexamined patent application No. H3-92966. That is, if the balance stored in the IC card is less than the amount of the transaction, the user of the electronic purse is informed that the balance is short and is urged to select whether the transaction is to be stopped, the amount to be paid using the IC card is to be changed or another transaction method, such as a regular credit card, is to be used to perform a flexible transaction.
Since the above-described prepaid card is usable only for payment for a specific service, a card for the amount of money corresponding to the service is prepared beforehand. Therefore, there are few occasions on which the balance is short. However, in the above-described electronic purse system, there is a great possibility that a shortage in the balance will occur at the time of payment due to the user forgetting to pay into his own electronic purse, and the shortage of a required amount to be paid for a transaction occurs because an electronic purse is utilized in many diverse fields. Therefore, in an electronic purse system, the balance in an IC card can be checked at any time using a portable balance display and other means, however, if the balance is short at the time of a transaction, the transaction using the electronic purse is not permitted.